【摘要】 多区循环流化床（MZCR）工艺可灵活调控聚丙烯的分子量分布，能制备分子量分布从极窄到极宽的均聚物与无规共聚物，所得产品具有良好的结构均匀性。该工艺常用Ziegler-Natta催化剂，其多活性位特征对表观聚合动力学具有显著影响。通过高温凝胶渗透色谱（HT-GPC）和高温核磁共振碳谱(¹³C-NMR)对两个工况的样品进行表征，获取了反应器出口产品的分子量分布和平均共聚组成数据，并构建了耦合热力学与多活性位配位聚合动力学的MZCR机理模型。通过工况1数据确定了多活性位个数和反应动力学参数，通过工况2对模型进行验证。结果表明：工况1建模最大相对误差不高于6.3%，工况2验证中所有误差均低于5.0%。本研究将多活性位机理与PC-SAFT方程耦合应用于工业规模模拟，为MZCR工艺的建模研究提供了理论支撑。更多还原

【Abstract】 The multi-zone circulating fluidized bed（MZCR） process enables flexible control over the molecular weight distribution of polypropylene, producing homopolymers and random copolymers with molecular weight distributions ranging from extremely narrow to very broad, exhibiting excellent structural uniformity. MZCR predominantly employs Ziegler-Natta catalysts, whose multi-active site characteristics influence apparent polymerization kinetics. High-temperature gel permeation chromatography（HT-GPC） and carbon-13 nuclear magnetic resonance(¹³C-NMR) were employed to characterize samples from two operating conditions. This yielded the molecular weight distribution, and average copolymer composition of reactor outlet products, enabling the development of an MZCR mechanism model incorporating thermodynamics and multi-site coordination polymerization kinetics. The number of active sites and reaction kinetic parameters were determined based on condition 1 data, and the model was validated using condition 2 data. Results indicate: the maximum relative error in modeling for operating condition 1 did not exceed 6.3%; all errors in validation for operating condition 2 were below 5.0%. This study couples the multi-active-site mechanism with the PC-SAFT equation for industrial-scale simulation, providing a theoretical basis for modeling research on circulating fluidized bed processes.更多还原